INTRODUCTION: There is growing use of nasal continuous positive airway pressure ventilation (nCPAP) for infants with bronchiolitis, based on clinical assessment of severity. Despite this there have been no studies which identify clinical predictors for the requirement of nCPAP.OBJECTIVE: To identify clinical factors in infants with acute bronchiolitis in the emergency department (ED), which might predict a requirement for nCPAP following admission.MATERIALS AND METHODS: Retrospective review of pediatric ED case notes was conducted on bronchiolitis admissions to one dedicated Paediatric ED over a 12-month period. Potential predictors were identified through literature review. Data extraction of predictors was carried out and recorded for each case. Logistic regression was conducted for each variable to identify statistically significant predictors of nCPAP requirement.RESULTS: Twenty-eight (17%) of the 163 admitted infants received nCPAP. The strongest predictors of nCPAP requirement in were as follows: oxygen requirement within the ED (P < 0.001), lower oxygen saturation (P < 0.001), younger age at presentation (P = 0.002), higher respiratory rate (P = 0.002), higher heart rate (P = 0.003), lower Glasgow Coma Scale score (0.006), and younger gestational age (P = 0.024).CONCLUSION: We have identified clinical variables that were predictive of nCPAP requirement in infants admitted to our unit with bronchiolitis, oxygen requirement in the ED being the strongest single predictor. This is the first such study in the UK, and we hope it may be a starting point for further work that may provide an evidence base to aid clinicians in predicting the use of nCPAP in infants with bronchiolitis.